Whoops, sorry! Misread that as Joss.
But true, the Steamborg normally gets to be the target of spells like Obey or Self-Loathing.
The flexibility is great with the Arachnids, especially since they always cause the threat of Self-Destruct for a free 2 Dg. But having them possibly getting picked off by your opponents range is bad also, since they are running around with only 3 Wd. I suppose this has a more situational answer anyhow, when in Step 5: Hire Crews of the encounter, just make the choice based on the terrain setup and the scenarios you and your opponent got and schemes you chose.